Grapes grew wild in the Catskill Mountains on the grounds of the family home in New York. They were, perhaps, of the varieties chronicled by Leif Erikson a thousand years ago and resembled the muscadines vining today through the Carolinas, though darker in color and carrying coarse, hairy leaves that disappointed Dad’s family, who loved to eat rice-stuffed grape leaves — but not these!
Their tendrils and tart-sweets twined over our lilacs and dogwoods and dangled in plain sight, luring Judith A. Moses to embark on a jelly journey. Small but mighty in flavor, each individual fruit contributed a pea-sized, midnight-violet skin, encapsulating a Halloweenie eyeball of pulp. With little pressure from thumb and forefinger, the innards launched delightfully out of the peel. We spent hours pinching the purples: plump, plump, to blast past a stockpot. Simmered and strained and sugared, they would foam up like an Icelandic volcano. Mom bottled the collective and we called it JAM.
That Icelandic volcano has sugary properties of its own.
Volcano rocks are distinguished by their ingredients and their temperature profile, and so were Mom’s sugar-based delights.
Deep inside the Earth, high temperatures stoke the melting of silicate sauces. Additional components, from iron and calcium to magnesium and water, adjust the melting point. Thus, different minerals in a rocktype heading for a volcano could melt at different temperatures and sort into separate fractions based on the surrounding temperature. Minerals with higher melting points would divorce from those that drip out, changing the chemical recipe of the original rock.
Likewise, the hot jellypot provokes melting of the sugar, aided, abetted and abutted by water. Hot water breaks wide sugar crystals into smaller mono bricks, wetting them into syrup then caramelizing with further heating as the water cooks out, crowding the sugar blocks together.
Bubble, trouble, toil and rubble: fillet of peptide, pucker of tannin, pigment of flavinoid, acid of tartar, sweetness of saccharide. The blend of plant components distinguishes the bouquet of a jelly. Pull of soil, succulent oil, fire burn and cauldron boil. In rocks, the blend of minerals distinguishes the color of cobble, the hardness of nodule, the technique of streak, the immensity by density.
Yet it is the relaxation of heat energy during cooling that is the royal ingredient of texture, be it in sugar or stone. Many liquids crystallize into solids by fitting recurrent units into a repetitive structure, stacking them, Lego-like, in a uniform pattern. In volcano rocks, a long, gradual cooling period enables block-by-block lock-in of lattice before freezing in place. Should those crystals break apart, they separate along clean, straight lines. Inside the cores of planets and asteroids, where cooling rates are ridiculously slow, perhaps just a few degrees per million years, even iron forms crystals.
But crystalizing takes time, and if cooled too quickly, solidification occurs before stacked structure. Quick quenching, when 2,000-degree magma meets 75-degree air, freezes a brickle crystal before it can drift into place, trapping it in a hodge-podge of tumbled Legos, causing brittleness and unfaceted rock properties such as the curvy cut of glassy obsidian.
In cooked fruits, sugar structure can tangle with threads of pulp and hinder crystal formation. Stringy molecules, such as chains of fruit pectin, often block the orderly growth of sugar grains into precise latticed structures. These strands also trap water, making a soft, glassy jelly that cleaves in curves rather than crystals when put to the toast knife. Beyond jelly, in a bubbling stockpot of syrup, eventually all water boils away, stiffening the flow of crystals before they can latch to the lattice, trapping them in a hodge-podge of tumbled Legos, solid but brittle, perhaps sprinkled with peanuts.
Silicate rocks are quite durable, and their silicate crystals can re-emerge 200 million years later milled into sand by weathering. Sand can be melted anew, like sugar, then cooled quickly into glass.
A wild place to find a grapey glass might be in a jam-up of JAM jams.
A wild place to find a fine epic sand story might be Kanab, Utah.
Kanab sand showcases both weathering and wizardry. A brief scramble up the pumpkin-spice rusts and tans of cross-bedded sandstone beside Route 89 displays silicate grains that once raged across an ancient desert, buried by subsequent dunes and cementing into stone. The Moqui Sand Caves are a set of holes dug by humans into a wall of this sandstone to mine the sand. The grit is so loosely attached to its stone that a single wizened finger-swipe or puff of windy weather causes a shower of grains to dislodge — perfect for easy access to truckloads of sand crystals, ready for hodge-podging like Legos to open a new window on the ways of the crystalline world.
